Guide wires are generally known in the art. Their use is, for example, in connection with treatment of coronary disease. As is conventional, a contrast media is used in connection with an x-ray of a blood vessel to show occlusion, however, without showing a cross section of a stenosis. Complicating the diagnosis of the problem is that different patients have different blood flow. Measurement of blood pressure is a way to diagnose the significance of the stenosis. In practice, a distal end of the guide wire is inserted into the body, for example into an opening into the femoral artery, and placed at a desired location. At the distal end of the guide wire is a miniature sensor arranged for measuring pressure. Further, once the guide wire is placed by the physician into the appropriate location, a catheter of appropriate type may be guided onto the guide wire. A balloon dilation may then be performed.
Electrical leads extending along the guide wire carry measurement signals from the sensor via connectors to a monitor for further processing. The guide wire is electrically connected through a male connector arranged at a proximal end of the guide wire, via a female connector, to the monitor. At the male connector, there are one conductor member arranged for each lead extending along, or inside, the guide wire. Insulating spacers are arranged to separate the conductor members. On insertion of the male connector in the female connector, the conductor members are brought into electric contact with corresponding female contact members.
When the physician places the guide wire into the appropriate location in the body, the male connector may be contaminated by, for example, dirt, fat, moist, etc., which is attached to the physician's fingers and deposited onto the male connector. Alternatively, body fluids such as blood may be deposited onto the connector when the guide wire is inserted in the body. In another scenario, to permit replacement or exchange of the catheter, the male connector is disconnected from the female connector and the catheter is removed over the guide wire. At that time, body fluids will be deposited directly onto the male connector and indirectly onto the female connector, via the male connector. Hence, the connectors may be contaminated by blood and other bodily fluids at the time the catheter is changed, and these body fluids will potentially alter the electrical properties of the connector. As a further consequence, the contaminations given above may deteriorate the insulation between the conductor members in the connectors, and measured values may become unreliable due to leakage currents flowing through the insulating spacers. Further, insulation may be deteriorated for other reasons, for example because of manufacturing defects.
A guide wire assembly with connectors is shown, for example, in U.S. Pat. No. 6,663,570, Mott et al. In U.S. Pat. No. 6,663,570, a system is disclosed for connecting a flexible elongate member arranged with an electrically operable sensor to a physiology monitor. The system comprises a flexible cable having an electrical conductor therein and a connector arranged on an end of the flexible cable for receiving an end of the flexible elongate member. A contact member in the connector is electrically connected to the conductor in the flexible cable to transfer data to the physiology monitor.
In this type of prior art guide wire assembly, bodily fluids and other contaminations can clearly cause electrical problems in the connector. Consequently, there remains a need for a connector which can be used with the restricted small size of a guide wire typically having a diameter of 0.35 mm, and which can be used in situations where there might be contamination by human or animal body fluid or contaminations such as dirt, fat or moist.